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Related papers: Deformations of nearly parallel G_2-structures

200 papers

We show that finite parallel transports of vectors in Riemannian spaces, determined by the multiplication law in the deformed groups of diffeomorphisms, and sequences of infinitesimal parallel transports of vectors along geodesics are…

Differential Geometry · Mathematics 2007-09-17 Serhiy E. Samokhvalov

We classify 7-dimensional cocalibrated $\G_2$-manifolds with parallel characteristic torsion and non-abelian holonomy. All these spaces admit a metric connection $\nabla^{\mathrm{c}}$ with totally skew-symmetric torsion and a spinor field…

Differential Geometry · Mathematics 2007-05-23 Thomas Friedrich

Motivated by known examples of Joyce structures on spaces of meromorphic quadratic differentials, we consider the isomonodromic deformations of particular second-order linear ODEs with rational potential. We show the infinitesimal…

Differential Geometry · Mathematics 2026-05-22 Timothy Moy

Algebraic structure of a class of differential equations including Heun is shown to be related with the deformations of sl(2) algebra. These include both quadratic and cubic ones. The finite dimensional representation of cubic algebra is…

Mathematical Physics · Physics 2013-04-09 Arunesh Roy , Abhijit Sen , Prasanta K. Panigrahi

In this continuation of \cite{BDS}, we investigate the deformations of holomorphic Cartan geometries where the underlying complex manifold is allowed to move. The space of infinitesimal deformations of a flat holomorphic Cartan geometry is…

Differential Geometry · Mathematics 2022-01-25 Indranil Biswas , Sorin Dumitrescu , Georg Schumacher

We compute the universal deformations of cuspidal representations $\pi$ of $\GL_2(F)$ over an algebraically closed field of characteristic $l$, where $F$ is a local field of residue characteristic $p$ not equal to $l$. When $\pi$ is…

Number Theory · Mathematics 2009-09-15 David Helm

We study the special algebraic properties of alternating 3-forms in 6 and 7 dimensions and introduce a diffeomorphism-invariant functional on the space of differential 3-forms on a closed manifold M in these dimensions. Restricting the…

Differential Geometry · Mathematics 2007-05-23 Nigel Hitchin

We study the $\rm{SU}(3)$-structure induced on an oriented hypersurface of a 7-dimensional manifold with a nearly parallel $\rm{G}_2$-structure. We call such $\rm{SU}(3)$-structures nearly half-flat. We characterise the left invariant…

Differential Geometry · Mathematics 2024-09-05 Ragini Singhal

We prove that the irreducible components of the space of framed deformations of a $2$-dimensional mod $2$ representation with scalar semi-simplification of the absolute Galois group of $\mathbb{Q}_2$ are in natural bijection with those of…

Number Theory · Mathematics 2016-01-01 Maurice Babnik

We exhibit the first examples of closed 7-dimensional Riemannian manifolds with holonomy G_2 that are homeomorphic but not diffeomorphic. These are also the first examples of closed Ricci-flat manifolds that are homeomorphic but not…

Algebraic Geometry · Mathematics 2020-05-11 Diarmuid Crowley , Johannes Nordström

We consider left-invariant (purely) coclosed G$_2$-structures on 7-dimensional 2-step nilpotent Lie groups. According to the dimension of the commutator subgroup, we obtain various criteria characterizing the Riemannian metrics induced by…

Differential Geometry · Mathematics 2023-05-02 Viviana del Barco , Andrei Moroianu , Alberto Raffero

The purpose of this article is to study the deformations of smooth surfaces $X$ of general type whose canonical map is a finite, degree 2 morphism onto a minimal rational surface or onto $\mathbf F_1$, embedded in projective space by a very…

Algebraic Geometry · Mathematics 2010-06-01 Francisco Javier Gallego , Miguel González , Bangere P. Purnaprajna

We study the problem of finding exactly marginal deformations of N=1 superconformal field theories in four dimensions. We find that the only way a marginal chiral operator can become not exactly marginal is for it to combine with a…

High Energy Physics - Theory · Physics 2014-11-21 Daniel Green , Zohar Komargodski , Nathan Seiberg , Yuji Tachikawa , Brian Wecht

We classify deformations of $\mathfrak{osp}(2|2)-$module structure on the spaces of symbols $\mathfrak{S}_d^2$ of differential operators acting on the space of weighted densities $\mathfrak{F}_{\lambda}^{2}$.

Representation Theory · Mathematics 2018-06-14 Mabrouk ben Ammar , Wafa Mtaouaa

We construct the deformation functor associated with a pair of morphisms of differential graded Lie algebras, and use it to study infinitesimal deformations of holomorphic maps of compact complex manifolds. In particular, using L-infinity…

Algebraic Geometry · Mathematics 2008-04-03 Donatella Iacono

This article deals with universal deformations of dihedral representations with a particular focus on the question when the universal deformation is dihedral. Results are obtained in three settings: (1) representation theory, (2) algebraic…

Number Theory · Mathematics 2020-04-10 Shaunak V. Deo , Gabor Wiese

We study the effective action for the integrable $\lambda$-deformation of the $G_{k_1} \times G_{k_2}/G_{k_1+k_2}$ coset CFTs. For unequal levels theses models do not fall into the general discussion of $\lambda$-deformations of CFTs…

High Energy Physics - Theory · Physics 2018-11-28 Konstantinos Sfetsos , Konstantinos Siampos

We prove the modularity of minimally ramified ordinary residually reducible p-adic Galois representations of an imaginary quadratic field F under certain assumptions. We first exhibit conditions under which the residual representation is…

Number Theory · Mathematics 2010-06-15 Tobias Berger , Krzysztof Klosin

Let K be an arbitrary number field, and let rho: Gal(Kbar/K) -> GL_2(E) be a nearly ordinary irreducible geometric Galois representation. In this paper, we study the nearly ordinary deformations of rho. When K is totally real and rho is…

Number Theory · Mathematics 2008-01-17 Frank Calegari , Barry Mazur

We define a deformation space of V. Lafforgue's $G$-valued pseudocharacters of a profinite group $\Gamma$ for a possibly disconnected reductive group $G$. We show, that this definition generalizes Chenevier's construction. We show that the…

Number Theory · Mathematics 2026-04-01 Julian Quast